General Information The flathead’s catfish head is broadly flattened, with a projecting lower jaw. Flathead catfish can reach up to 3 to 4 feet, and weigh well over 100 lbs. It has scale-less skin, and long, sharp spines on the dorsal fin, with one on each side of the pectoral (shoulder) fin. They are usually a pale yellow to light brown on the back and sides, with a highly molted black or brown covering. (1)
DETAILED DESCRIPTION Males select hollow logs, caves or areas beneath the banks for their nest sites. Males may even improve their selected sites by creating shallow depressions for the females to lay their eggs. Egg number varies greatly depending on female size, but the average is up to 100,000 eggs at a time (1), but only a small number will survive (2). If females have been eating poorly, their bodies may conserve resources by not releasing eggs. Poor overall health and certain environmental conditions such as drought or flood can reduce flatheads' ability to spawn. Males defend their nest and eggs aggressively. They will fan the nest with their tails to keep the eggs clean and provide them with oxygenated water (1). After the eggs hatch, the fry remain in a compact school around the nest for several days, guarded by the male fish (2).
Although most catfish are scavengers, flatheads prey on only live fish. When they are young they eat mostly worms, insects, and crayfish. Larger flatheads almost entirely feed on bass, fish-shad, suckers, and even catfish of their own. (1)
Flatheads are known for their aggressive eating habits, and large size. They compete with many native species for food, which have lead native species to slowly diminish. Habit && Distribution Flathead catfish are found in large rivers, streams and lakes. They prefer deep, sluggish pools, with logs and submerged debris cover (3). Found in Central America (4), they are Mississippi and Ohio River natives. They can now be found from the lower Great Lakes through the Mississippi River watershed to the Gulf States.
Impacts Ecological Impact:Flatheads compete with native fish populations for food and habitat. Flatheads introduced in Georgia and North Carolina Rivers have eliminated native catfish populations and were found to prey heavily on crayfish, crabs, and shad. (3) Human health risks:Flathead meat tends to accumulate toxins such as PCBs. For this reason, The Commonwealth of Pennsylvania advises eating no more than one meal a month of flatheads caught in the lower Schuylkill. (3)
Economic impacts:Flathead catfish may have an economic impact on the blue crab industry as well as shad, sturgeon, and striped bass. (3)
History Flatheads were intentionally stocked into new areas by anglers. They were moved from the Mississippi River area, to non-native areas from the beginning of the 1950's. (4)
Control Measures In some areas to help control the amount of flatheads, fishers are urged not to release the Flathead Catfish when caught.
Flathead Catfish (Pylodictis Olivaris)
General InformationThe flathead’s catfish head is broadly flattened, with a projecting lower jaw. Flathead catfish can reach up to 3 to 4 feet, and weigh well over 100 lbs. It has scale-less skin, and long, sharp spines on the dorsal fin, with one on each side of the pectoral (shoulder) fin. They are usually a pale yellow to light brown on the back and sides, with a highly molted black or brown covering. (1)
DETAILED DESCRIPTION
Males select hollow logs, caves or areas beneath the banks for their nest sites. Males may even improve their selected sites by creating shallow depressions for the females to lay their eggs. Egg number varies greatly depending on female size, but the average is up to 100,000 eggs at a time (1), but only a small number will survive (2). If females have been eating poorly, their bodies may conserve resources by not releasing eggs. Poor overall health and certain environmental conditions such as drought or flood can reduce flatheads' ability to spawn. Males defend their nest and eggs aggressively. They will fan the nest with their tails to keep the eggs clean and provide them with oxygenated water (1). After the eggs hatch, the fry remain in a compact school around the nest for several days, guarded by the male fish (2).
Although most catfish are scavengers, flatheads prey on only live fish. When they are young they eat mostly worms, insects, and crayfish. Larger flatheads almost entirely feed on bass, fish-shad, suckers, and even catfish of their own. (1)
Flatheads are known for their aggressive eating habits, and large size. They compete with many native species for food, which have lead native species to slowly diminish.
Habit && Distribution
Flathead catfish are found in large rivers, streams and lakes. They prefer deep, sluggish pools, with logs and submerged debris cover (3).
Found in Central America (4), they are Mississippi and Ohio River natives. They can now be found from the lower Great Lakes through the Mississippi River watershed to the Gulf States.
Impacts
Ecological Impact: Flatheads compete with native fish populations for food and habitat. Flatheads introduced in Georgia and North Carolina Rivers have eliminated native catfish populations and were found to prey heavily on crayfish, crabs, and shad. (3)
Human health risks: Flathead meat tends to accumulate toxins such as PCBs. For this reason, The Commonwealth of Pennsylvania advises eating no more than one meal a month of flatheads caught in the lower Schuylkill. (3)
Economic impacts: Flathead catfish may have an economic impact on the blue crab industry as well as shad, sturgeon, and striped bass. (3)
History
Flatheads were intentionally stocked into new areas by anglers. They were moved from the Mississippi River area, to non-native areas from the beginning of the 1950's. (4)
Control Measures
In some areas to help control the amount of flatheads, fishers are urged not to release the Flathead Catfish when caught.
Works Cited1. "Flathead Catfish (Pylodictis olivaris)." Texas Parks and Widlife. 11 Sept. 2008. 17 Nov. 2008 http://www.tpwd.state.tx.us/huntwild/wild/species/catfish/.
2. "Flathead Catfish." Ace Basin Species. 17 Nov. 2009 http://www.dnr.sc.gov/marine/mrri/acechar/specgal/flathead.htm.
3. "FLATHEAD CATFISH." Aquatic Invasive Species of Pennsylvania. 17 Nov. 2008
http://www.pserie.psu.edu/seagrant/ais/watershed/catfish.htm.
4. "Aquatic Species." Invasive Species Info. 19 June 2008. United State Department of Agriculture. 17 Nov. 2008 http://www.invasivespeciesinfo.gov/aquatics/flatcatfish.shtml.